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Detection Microcalcifications in Mammograms Using Wavelet

Reporter : 陳宏維Date : 2007/05/22

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Outline

Introduction

Fourier TF. V.S. Wavelet TF.

Two-Dimension Wavelet Transform

Performance

Classifier

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Introduction

(a) Fatty (b) Fatty-glandular (c) Dense-glandular

乳房內部成份 : 脂肪、腺體、結締組織鈣化形成 : 乳汁沉澱或細胞壞死亮度 : 脂肪 ＜ 腺體及結締組織 ≦微鈣化組織

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One-Dimensional Statistics

(a) One-Dimensional Curve

(c) Gaussian Object

(b) ROI

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Fourier TF. V.S. Wavelet TF.

(c) Fourier Coefficient

Discontinuity

(b) Wavelet Coefficient

}2,40|{)sin( tttty

Original Signal:

(a) Original Signal

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Two-Dimension Wavelet Transform

(a) Analysis

(b) Synthesis

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2

2

2

22

2

2

2

2

2

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Wavelet Octave

(a) Wavelet Octaves

(b) Original Image

(c) Original Image

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Performance

True Positive (TP) : 系統將病變組織判斷為病變組織。 True Negative (TN) : 系統將病變組織誤判為正常組織。 False Positive (FP) : 系統將正常組織誤判為病變組織。 False Negative (FN) : 系統將正常組織判斷為正常組織。

診斷 辨識

病變組織 正常組織

病變組織 TP FP

正常組織 FN TN

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Wavelet Function

(a) Original Image

(d) BAUD 4(b) BAUD 4 Filter

(c) BAUD 20 Filter(e) BAUD 20

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Classifier

)1()()(2)()())()(( max

min

max

min

max

min

222 dxxxdxxdxxdxxx xx

xt

tx

xx

)2(0)()(max

min dxxxx

x

x (Gray Level Value)

α(x) β(x)

t xmaxxmin

α(x) : pdf for the breast tissue

β(x) : pdf for the microcalcifications

Renyi’s entropy :

)3(]})(ln[])(ln[max{ 22 max

min dxxdxxArgt x

ttx

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Detection

(a) Original Image (b) Truth Image (c) Detected Microcalcification

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Reference

1. K. Thangavel, M. Karnan, R. Sivakumar, and A. Kaja Mohideen, “Automatic Detection of Microcalcification in Mammograms- A Review,” ICGST, 2006.

2. Giuseppe Boccignone, Angelo Chianese, and Antonio Picariello, “Computer aided detection of microcalcification in digital mammograms,” Computer in Biology and Medicine, 2000.

3. Robin N. Strickland, Senior Member, IEEE, and Hee Π Hahn, “Wavelet Transforms for Detecting Microcalcification in Mammograms,” IEEE Trans. Med. Image, Vol. 15, No. 2, Appil, 1996

4. Ted C. Wang, and Nicolaos B. Karayianmis, “Detection of Microcalcification in Digital Mammograms Using Wavelets,” IEEE Trans. Med. Image, Vol. 17, No. 4, August, 1998

5. 繆紹剛 , ” 數位影像處理 活用 --Matlab”, 全華科技圖書股份有限公司 , 2002